Hexathiophenalenylium Cations: Syntheses, Structures, and Redox Chemistry

Preparations of two hexathiophenalenylium compounds as stable salts from the reaction of 3,4,6,7-tetrathio-9-hydroxyphenalenone with Lawesson’s reagent have been reported. The presence of three disulfide linkages on the periphery of the core phenalenyl unit is confirmed by X-ray crystallographic characterizations. Electrochemical cell potentials are lower than those of related dithio- and tetrathio-bridged phenalenyl radicals, and the hexathiophenalenyl radical shows a strong electron paramagnetic resonance (EPR) signal in the solid state.